Waterproof cement.



UNITED STATES PATENT OFFICE.

HARRY B. CHALMERS, 0F DEDHAM, MASSACHUSETTS.

WATERPROOF CEMENT.

No Drawing.

To all whom it may concern:

Be it known that I, HARRY B. CHALMEas, a citizen of the United States,and a resident of the city of Dedham, in the county'of Norfolk and Stateof Massachusetts, United States of America, have invented" certain newand useful Improvements in Waterproof Cement, of which the following isa specification.

My invention relates to a new com osition of matter which is useful forcementlng, and which is especially applicable for cementing belting ofleather or other material, and for many other uses where a cement whichis not affected by moisture is desired.

To these ends my invention resides in the combination of chemicalmaterials which I will describe in the following specification, andwhich-I will set forth in the appended claims.

Nitro-cellulose dissolved in suitable solvents has been used as awater-proof cement to a considerable extent and to the great benefit ofmanufactures, especially to the belt-manufacturers trade. Suchcompositions of matter had their restrictions and objectionable featuresamong which is their inflammability and consequent danger in use. Toovercome this objectionable feature of the aforesaid compositions ofmatter, and for the purpose of improving upon compositions of thischaracter, I have invented the water-proof cement and the process ofmanufacturmg said cement which I will now proceed to describe.

Instead of nit-rating the cellulose I first treat it with acetic acidtoform an acetate of cellulose. Or, if desired, the tetra-acetate ofcellulose may be used- The latter ma-' terial is perhaps more available,but the maker of the cement is more limlted as to solvents than he iswith the acetate. Acetone or chloroform are satisfactory solvents andthese may be mixed with fusel-oil, acetic acid, amyl acetate,nitrobenzol, or other chemical for purposes of lessenin the cost ofmanufacture, or for retarding t e drying qualities of the finishedproduct. Its dura- Specification of Letters Patent.

Application filed November 29, 1908. Serial No. 580,310. I

Patented Oct. 6, 1914.

bility is also enhanced by the use of a softening agent, such forexample, as a relatively small guantlty of castor-oil, carbolic acid,creosote, naphthalin, camphor, or non-volatile ester of the fatty or'aromatic acids. Any of these may be used by themselves for this purpose,or two or more of them may be used together if so desired.

Many variations of the above chemical materials may be used withoutdeparting from the principles of this invention, to produce acomposition with the desired characteristics and qualities. Merely as aconcrete example of one exemplification of this invention, the followingingredients and proportions are set forth. Tetra-acetate of cellulose,one pound, dissolved in a mixture of one half of a gallon of chloroformand one half of a gallon of acetone, to which has been added one percent, castor-oil and I one per cent. carbolic acid by weight.

The composition of matter herein" described is especially made for thepurpose of a water-proof cement for belting and other articles, but I donot, of course, mean -to limit myself to thisspecific use, as it isobviousl applicable for other uses such as that of coating leather ortextiles, or for coating wires for insulating purposes.

What I claim.is. 1. A cement comprising tetra-acetate of cellulose.dissolved in a mixture of chloro form and, acetone, and a smallpercentage of castor oil and carbolic acid.

2. A cement comprising tetra-acetate of cellulose, one pound, dissolvedina mixture of one half of a gallon of chloroform and one half of agallon of acetone, said mlxtune containing by weight one-per cent.castor 011 and one per cent. carbolic acid.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

HARRY B. CHALMERS Witnesses: I

GORDON STEWART, OSWALD Hammer.

